Megane 2003 1.9dci Electronic fault?

Hi,
i am in panic! Can someone help with guidance!

Mi megane 1.9dci 2003 was washed in automatic car wash. upon arrival at home approx 3mls away, displayed "electronic fault" all the lights came on and the engine refused to stop running. after 45min, engine stopped by its self (do not know why or how), but lights and windscreen wipers wont come off until breakdown Co disconnected the battery.
... well took the car the local renault garage and i have just been quoted £2500.00 to repair it, and I quote:
"UPC has water ingress into the unit. This has also damaged the engine and body wiring looms of the car.
cost of repair:
parts £1413.79
labour ££1104.00

Has someone had similar problem? Are they taking me for a ride?
Any solutions available?
... please help!